A research on the influence of G-CSF mobilization on donor's peripheral blood MDSCs and its relationship with patient prognosis.

OBJECTIVE: To discuss the effects of mobilization of healthy donors with granulocyte colony-stimulating factor (G-CSF) on the absolute values and functions of myeloid-derived suppressor cells (MDSCs) and subpopulations of M-MDSCs and P-MDSCs in their peripheral blood. In addition, this study also aims to investigate the impacts of the adoptively transferred MDSCs from the grafts to the patients on their prognosis and immune reconstitution. METHODS: The selection of 72 donors and 72 patients were conducted for allogeneic hematopoietic stem cell transplantation (allo-HSCT) from August 2022 to December 2022 at Lu Daopei Hospital in Beijing, China. Statistical calculations were performed by Wilcoxon signed-rank test, Kruskal Wallis test, χ2 test, Kaplan Meier test, and log-rank test to analyze the data. RESULTS & CONCLUSION: G-CSF induced significant amplification of MDSCs in the peripheral blood of donors in percentage and absolute values. Whether the level of P-MDSCs in patients conducted for the adoptive transfer of P - MDSCs is higher than 3.7× 107/kg or lower than 1.4× 107/kg leads to a poor prognosis of the patients. Ensuring a balanced state of MDSCs is crucial for effective immunotherapy. Transferring a high level of MDSCs from the graft to the patient's body is advantageous for the development of MDSCs while simultaneously inhibiting the proliferation of lymphocyte subgroups.

Twenty-four-color full spectrum flow cytometry panel for minimal residual disease detection in acute myeloid leukemia.

Full spectrum flow cytometry brings a breakthrough for minimal residual disease (MRD) detection in acute myeloid leukemia (AML). We aimed to explore the role of a new panel in MRD detection. We established a 24-color full-spectrum flow cytometry panel. A tube of 24-color antibodies included CD45, CD117, CD34, HLA-DR, CD15, CD64, CD14, CD11c, CD11b, CD13, CD33, CD371, CD7, CD56, CD19, CD4, CD2, CD123, CD200, CD38, CD96, CD71, CD36, and CD9. We discovered that when a tube meets 26 parameters (24 colors), these markers were not only limited to the observation of MRD in AML, but also could be used for fine clustering of bone marrow cells. Mast cells, basophils, myeloid dendritic cells, and plasmacoid dendritic cells were more clearly observed. In addition, immune checkpoint CD96 had the higher expression in CD117+ myeloid naive cells and CD56dimNK cells, while had the lower expression in CD56briNK cells in AML-MRD samples than in normal bone marrow samples. CD200 expression was remarkably enhanced in CD117+ myeloid naive cells, CD4+ T cells, T cells, activated T cells, CD56dimNK cells, and CD56briNK cells in AML-MRD samples. Our results can be used as important basis for auxiliary diagnosis, prognosis judgment, treatment guidance, and immune regulation in AML.

Cytoplasmic CD79a is a promising biomarker for B lymphoblastic leukemia follow up post CD19 CAR-T therapy.

Minimal residual disease (MRD) detection is an important prognostic parameter in patients with refractory or relapsed B-cell acute lymphoblastic leukemia (R/R B-ALL). CD79a has been reported to exhibit a high degree of linage-specificity for B-cell differentiation, with a specificity of 88% and a sensitivity of 100%. In this study, we investigated the efficiency and prognostic role of cytoplasmic CD79a (cCD79a) antibody-gated multicolor flow cytometry (MFC) in MRD detection in patients with B-ALL who received CD19-targeted chimeric antigen receptor (CAR) T-cell therapy bridging to allogeneic hematopoietic stem cell transplantation (allo-HSCT). The retrospective analysis was carried on to 59 patients who accepted allo-HSCT after CD19-CAR-T infusion from June 2016 to May 2017. The MFC MRD statuses before and after allo-HSCT were both strongly correlated with the transplantation prognosis, the MFC panel with cCD79a gating can effectively monitor MRD after CD19 CAR T-cell therapy and predict the prognosis after allo-HSCT. Trial registration: ClinicalTrials#: ChiCTR-IIh-16008711.gov: NCT03173417. Registered 30 May 2017 - retrospectively registered, https://www.clinicaltrials.gov/.

Analysis of the Expression of the TRBC1 in T lymphocyte tumors.

T cell therapy represents a new class of immunotherapies garnering considerable attention. T cell receptor beta chain constant region 1 (TRBC1) is partially expressed in subsets of normal T cells. However, the immunotherapy of T lymphocyte tumors is rarely validated in clinical trials. Here, we aim to explore whether TRBC1 is a promising target for the immunotherapy of T lymphocyte tumors. This study examined TRBC1 expression in 25 healthy bone marrow samples, 39 patients with T-lineage acute lymphocytic leukemia (T-ALL), 4 patients with mature T cell neoplasms, and 5 patients suspected with mature T cell neoplasms with evidence of T cell neoplasia. Moreover, the expression of TRBC1 was evaluated by flow cytometry and through PCR detection of TCR gene rearrangements. The expression of monophasic TRBC1 was identified in all 25 normal bone marrows (23.83% ± 2.74% positive rate). The expression of TRBC1 was positive in 5 patients (12.8%) among the 39 T-ALL patients. TRBC1 was partially expressed in 1 patient (25%) with T cell non-Hodgkin's lymphoma (T-NHL) and in 1 patient (20%) suspected to have T-NHL. Healthy donors showed a pattern of partial expression and patients with T-lymphocyte tumors showed a polytypic TRBC1 expression pattern. Thus, TRBC1 may be a diagnostic and therapeutic marker for T lymphocyte tumors.